Fuzzy relation equations and causal reasoning (Q1920315)

One of the ways to treat diagnosis problems is to relate them to particular relations between the ``manifestations'' and the ``diagnoses''. For the case of incomplete or uncertain informations different approaches have been proposed which relate to fuzzy relations and fuzzy relations equations. A careful analysis of the situation leads the authors to an even more general approach: they argue for using twofold fuzzy sets and twofold fuzzy relation and motivate this by ideas from possibility theory.